1. Field of the Invention
The invention relates to a lighting and/or signaling module, notably for a vehicle. The invention also relates to a mount for a lighting and/or signaling module and to a lighting and/or signaling device comprising the module and/or the mount.
2. Description of the Related Art
The use of light sources of the light-emitting diode (LED) type is becoming increasingly commonplace in motor vehicle headlamps and signaling lights. LEDs have an appreciably longer life than incandescent bulbs, specifically having a standard life in excess of 10,000 hours, sometimes of as much as 35,000 or even 50,000 hours, which is distinctly longer than the life of a motor vehicle. The life of an LED is, however, closely connected to its operating conditions, namely its operating temperature and the current passing through it. These operating conditions are generally so well controlled that the LEDs fitted in vehicle headlamps and signaling devices still have a life which in theory is longer than the life of the vehicle and therefore as a general rule they cannot be removed or replaced.
The same is not true of vehicle headlamps and signaling devices that use conventional incandescent bulbs that need to be easy to replace. Regulations, notably European regulations, regarding vehicle lighting and signaling have also recently ruled that the user of the vehicle has to be able to access the conventional bulbs in order to replace them.
The life of the LEDs fitted in vehicle headlamps and signaling devices can also be influenced, and more particularly shortened, as a function of various parameters essentially connected with their direct environment. Given that the use of LEDs in vehicle lighting and signaling has become the trend only recently, there is currently very little experience regarding the long-term integrity of LEDs under such operating conditions. However, it is the commonly held view that there is a risk that faults will occur over the course of time and that replacing LEDs may prove necessary.
Patent document WO 2006/066531 A1, which is equivalent to U.S. Patent Publication No. 2008/0130308, which issued as U.S. Pat. No. 7,806,562, discloses a quick-fit light source module of the LED type. In addition to having one or more light sources of the LED type, this module comprises a cooling radiator that cools the light source or sources and a quick-fastening device of the bayonet type. This teaching is attractive from a standpoint of ease of fitting, notably since the assembly comprising the light source(s) and corresponding radiator can be quickly and easily replaced. However, replacing one or more light sources in a lighting and/or signaling module, particularly a headlamp, causes a disturbance to the beam alignment. This is particularly true in the case of LED headlamps with beam cutoff. Specifically, the position of the light source has a direct impact on the cutoff. The solution proposed in that document therefore does not allow the user of the vehicle to replace the light source because subsequent scrupulous realignment would then be necessary. Such alignment does not fall within the scope of a routine vehicle service. The vehicle headlamp will therefore have to be removed.
Patent document FR 2 917 348 A1 describes a motor vehicle lighting and/or signaling device in which the light source is carried by a mount that is removable with respect to the housing of the device. More specifically, the glass of the device comprises an opening through which the light source and its mount are arranged. The light source essentially illuminates in an opposite direction to the direction of lighting and/or signaling of the device, a reflector of the parabolic type being positioned in the housing facing the light source so as to reflect the rays emitted by the source in the main direction of lighting and/or signaling of the device. Access to the light source is had from outside the device and outside the vehicle. This arrangement has the advantage of not requiring there to be an empty space into which to fit the hand of someone working on the headlamp or a tool used by such a person when replacing the light source. However, this fitting is essentially limited to light sources of the incandescent type. This is because light sources of the LED type are arranged on a printed circuit (PCB or printed circuit board) equipped with a radiator for cooling the LED or LEDs. The mounting provided for in this teaching is difficult to apply to a light source of the LED type because of the amount of space that these components occupy.
Patent document FR 2 727 190 A1 describes a motor vehicle headlamp in which the housing comprises a rear cover pivot-mounted on the housing. Opening the housing by pivoting the cover provides access to the main light source. The cover also supports an additional light source which acts as a position light. The technical solution divulged in that document is attractive from the standpoint of the ease of replacement of the light sources but is difficult to apply to light sources of the LED type.
In general, it should be noted that the architecture of light sources of the LED type is radically different from that of light sources of the incandescent type. As already mentioned, the LEDs are usually mounted directly on a board (PCB) which is provided with one or more radiators for cooling the LED or LEDs. This arrangement gives the LED and its equipment a certain bulk. Furthermore, certain headlamps or rear lights may have arrangements of LEDs that give them an individual nature or even a “signature”. Replacing one or more of the LEDs of such a lighting device may entail removal of the device so that work can be carried out at a specialist workshop.
What is needed, therefore, is a solution for replacing LED that overcomes one or more of the noted disadvantages.